Slag cement and process of making the same.



HANS KUHli, OF BLANKENESE,

MENTS, TO THE ATLAS PORTLAND CEMENT .coirrANY, or NEW tions are employed so 'lION OF PENN SYLVANIA.

NEAR- HAMBURG,

nnrrsn srlrrns rA'rnN r enrich.

SLAG cat/mun AND PsooEss or menrnc 'rnn SAME.

To all whom itmay concerm.

Be it known that l, l-l'ANs KUHL, a subject of. the King of Prussia, and resident of- Blankenese, near Ham "urg, German Empire, have invented certain new and useful improvements in Slag Cement and Processes of Making the Same, of which the following is an exact specification.

This invention relates to slag cement and relates especially to cement composed sub stantially of basic blast furnace slag with which, substantially non-hygroscopic addias to be capable of producing free caustic alkali in connection with theslag material when the cementis moistened with water in the customary inanner of utilization} Basic blastfurnace slag containing about or so of lime may be converted into asubstantially'yitreous or inert slag materia by water granulation and drying or by the well known air granulatingor disintegrating proccesses, such'as those using air or steam jets.

Specification of Letters Patent. Application file'd July 3, 1907. Serial No. 381,960.

This vitreous inert slag material usually 'hardens only very slowly and imperfectly at ordinary temperatures and gives only a cement is moistened.

' dratesof the alkaline earths slight rise ,of temperature. when ground, moistened and treated with carb'on-dioxid. This vitreous basic slag or slag material comprising the same may, however, be very iinely ground and suitable substantially nonhygroscopic accelerating and developing material incorporated therewith which when the with water for use proalkali in connection with the slag material by chemical reaction. Such added materials should preferably comprise suitable accelerating material contai ing some caustic alkali salt material, such as sodium sulfate or sodium carbonate, or suitable mixtures of the same to the extent of 'one or two per cent. of the slag. oping material should be some suitable basic material such fo example, as oxids-or bywhich is capable of reacting-with the other ingredients of the cement when moistened at ordinary temperatures so as to? develop free caustic alkali, 'ireferably containing potassium or sodium l'iydrate. l or exainple, calcium hydrate to three per cent. of the may be used as the deduces free caustic ground" slag material iSultate s oi-gthecaustic alkalies are "espe The devell atented Oct. 13,1908.

cially desirable for the accelerating material because in caselime is used as the developing material the reaction occurring when the cement is moistened for use produces calcium sulfate which is desirable as a regulating agent and for other purposes. By properly selecting the proportion of su accelerating material-used the desired regulation of the setting and the strength of the cement at various times can be secured. It is, of course, apparent that where the accelerating and developing materials added to the slag are substantiallynon-hygroscopic, that is, where they are not objectionably water-absorbing or hygroscopic under commercial conditions the cement will have good keeping qualities. Even after being stored for many months slag ccmentcf this'character has 'roved to be fully equal to'the best lfa'tes in the- GERMANY, ASSIGNOR, or MESNE ASSIGN- YonK, N. v, A CORPORA- Portlan cements in its constancy of volume,

setting properties the test pieces are Having described this invention in connec tion with a number of illustrative in redients 'and proportions,to the details of w ich disclosure this invention is not, of course, to be limited, what is claimed as new and what is desired tobe secured by Letters Patent is set forth in the appended claims. 4 i 1. The cement comprising vitreous basic blast furnace slag with which not more than "a few per cent. eluding sodium sulfate and sodium carbonate and not more than afew ing material including calcium hydrate have been incorporated so as to be capable of producing free caustic alkali in connectionwith the slag material when the cement is mois tened for use.

2. The cement comprising vitreous basic blast furnace slag with which not more than a few per cent. of accelerating material including sodium sulfate and sodium carbonate and notmore than a few percent. of developin material including free basic material have been incorporated so as'to be capable of producing free caustic alkali in connection with the slag material when the cement is moistened for use.

and strength both whenv kept in air and in waten.

of accelerating material, in-

per cent. of, developv 'The cement comprising vitreous blast emcee eluding free basic .Ineterial have been ili 70fmaterial when the cement is moistened for use.

D material With which not more than a few per cent. of substantially non-hygroscopic. accelerating material including caustic alkali seltineterinl endnot more than n. few per Gent. of developing material have been incorporated so as to he capable of producing free caustic alkali 111 connectuni with the slug;

use.

5. The cement comprising vitreous slog material with which not more than :1. low per cent. of substantially non hygroscopic nuibeen incorporated so as to be cnpeblo'of pro ducing free caustic alkali in connection with the slw n'interiel when the cement is moistened for use to accelerate, and

intensify the setting properties of the cement.

with which. not more than a, few per cent. of substantially non-hygroscopic. added mate" rial has been incorporated so as to be cnpn- .ble of producing free caustic allqnli material in. connection with said silicate meteriitl \i'hen the cement is moistened for use to accelerate end intensify the setting properties of the cement.

7. The cement comprising "vitreous hnsic blast furnace slag with which not more than n few per cent. of substenti lly nowhygrm svopic material comprising caustic nlloili mm tcriel has been added so as to secure the pres ence of free alkali nmteriiil in connection ith the slag when the cement is moistened for use to accelerate and intcnsilfi; the setting properties of the cement.

3. The cement pr which eonsistsdjn adding to vitreous basic blast furnace slag not more than c. few per cent. of substantially non-hygroscopic material comprising caustic allieli material so as to secure the presence ol free caustic alkali in connection with the slag material when the cement is zoistened I ting properties of the forusc to nceeleriitte end intensify thh se1-- cement.

The cement proce s which consists in incmpon'din; with vitreous basic blast l'ur necrslng not more than it few per cent. cl 4. The cement comprising vitreous slaw substantially iniii-hygroscopic material so as it). The cement pr cess which consists in incorporatn r with vitreous litbllu hlesl l'urnccc slog not more than :1. low per rent. of

V subsinntizdly uo:i-liy; 'o:-i ipic nnrlm'iul so as material when the cement 1s nu-istened 'lor incorpm'nlingr with basic blast furnace slog teruil includu'ig caustic alkali material has nmteriol not more than 22 ion per cent. ol 1141- celernling materiel including usull'nte ol' :1

Q with the slug material when the cement is 6. The cement com rising silicate runtcriul i'noistcnml for use.

1.12. The cement process which consists in inc; 'porutinsr with basic blast l'urnoeo sing materiel not more than u l'cv. per cent. of ncceleretingr l1l 2iit.le1l including sodium sulfate and not more than u low per cent. of basic V .eevelopingr nuiteriul so as to prmluco tree ceustic :lllidii in connection with said sodium curhonzute end not more than o for. per cent. of developing met-crud including calcium hydrete so as to produce free oustinalkali in connection. witi sold slog HULlOL'HLl when the cement moistened for one.

In witness whereof I have hereunto set my hand in the presence of two \vitne l HANS Kil -Hi1. Witnesses Enuestr H. L. IflUMMENuoFF, Orr'o WI HELL .ICZ:L 

